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NEW CITRUS CREATIONS OF THE DEPARTMENT OF 

AGRICULTURE. 



HERBERT J. WEBBER and WALTER T. SWINGLE, 

Vegetable Puthohxjmd and Physiologiral Jnrestigations, 
Bureau of Plant Industry. 



[Reprint krom Yearbook of Department of Agricultckk for 1904.] 



^-^ 



uG 7 » 
D.otO. 






AUG 7 1907 



AUG 7 
AUd).r'D. 
D. Of' D. 






CONTENTS. 



Page. 

Introduction 221 

Production of hardy citrus fruits 223 

The citrange, a new group of citrus fruits ^ ^ 227 

Ru.«k citrange 228 

Willits citrange _. 229 

How hardy is the citrange 231 

Of what value is the citrange 234 

The tangelo, a new group of loose-skinned citrus fruits 235 

The Sampson tangelo 236 

Uses of the tangelo 237 

New tangerine oranges 238 

The Weshart tangerine „ 238 

The Trimble tangerine 238 

General qualities of new tangerines 239 



ILLUSTRATIONS. 



PLATES. 

Page. 

Plate X. Branch of trifoliate orange 224 

XI. Hybrid seedling of common orange (female parent) and trifoliate 

orange (male parent) 228 

XII. Fruits of Rusk citrange and trifoliate orange 228 

XIII. Fruits of Rusk and Willits citranges, with trifoliate orange for com- 

parison ^. 228 

XIV. Seedling hybrids of trifoliate orange crossed with pollen of the 

eoonnion orange 230 

XV. Seedlings of citrus hybrids, showing relative vigor of true and false 

hybrids 230 

XVI. Willits citrange 230 

X VII. Sampson tangelo 236 

XVIII. Sampson tangelo, showing easily removable rind 236 

XIX. Sampson tangelo and ordinary pomelo 236 

XX. Weshart tangerine 238 

XXI. Group of Weshart tangerines, with parent varieties 238 

XXII. Trimble tangerine 238 

TEXT FIGURES. 

Fig. 12. Three seedlings grown from a single seed of a hy])rid 226 

13. Rusk citrange and lemon, showing comparative amount of juice from 

fruits of same volume " 234 

III 



NEAV CITRUS CREATIONS OF THE DEPARTMENT OF 
AGRICULTURE. 

By Herbert J. Webber, in Charge of Ixiboratory of Plant Breeding, and Walter 

T. Swingle, in Charge of Laboratory of Plant Life History, 

Vegetable Pathological and Physiological Investigations, Bureau Plant Industry. 

Introduction. 

For a period of five 3'ears, from November, 1S92, to October, 1897, 
the writers were associated in the study of diseases of citrus fruits in 
Florida, being located at Eustis, in the central part of the State. A 
careful study was made of the varieties cultivated and of the industry 
in general, primarily as a basis for an intelligent investigation of the 
diseases and methods of their control. In the course of these studies 
the attention of the writers was early drawn to the desirability of 
breeding more varied and improved sorts. 

An examination of the manner of origin of the various native sorts 
shows that in almost all cases they originated as accidental seedlings. 
Some growers made hybrids and used S3'stematic methods of breeding, 
but the number of fruits which have originated in this wa}' are very 
few indeed. The long time required to bring seedlings to bearing, 
the cost of cultivation and manuring, and the uncertainty of results 
have deterred growers from experimenting very extensively in this 
field. Owing to these difficulties, it seemed from the nature of the 
case that the investigations should ])e undertaken b}' the National 
Department of Agriculture, in order that the necessar}' funds could 
be provided and that the work could be carried on continuously for a 
series of years. This course was approved, and, under instructions 
from the Secretary of Agriculture, the writers, under assignment of 
Dr. B. T. Galloway, now Chief of the Bureau of Plant Industry, in 
the winter of 1892-93 made a careful study of the various citrus 
varieties and began the work of hybridization as rapidl}' as the time 
at their disposal would permit. These first attempts were largely pre- 
liminary, and most of the seedlings obtained were lost in the great 
freeze of 1S94-95, which killed to the ground all orange trees in the 
northern and central parts of Florida. This seriously interrupted 
the work and compelled its temporary abandonment, owing lo the fact 
that no groves could be found in the State furnishing the conditions 
necessary for carrying on hybridization. The experiments were taken 

221 



222 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 

up again in the winter of 1896-97, when the writers made an extensive 
series of crosses at Eustis and Braidentown, being assisted in the work 
by Mr. Otis H. Gates. Again, in the springs of 1898 and 1899, one of 
the writers made further crosses which resulted in greatly increasing 
the number of h^^brids. There have now been produced a total of 
1,780 hybrids, and these are being grown and tested under general 
instructions from Mr. A. F. Woods, Pathologist and Physiologist of 
the Bureau of Plant Industry. 

In all of the operations of hybridization the greatest care was 
taken to avoid contamination with pollen from other sources. In all 
cases buds were selected for hybridizing before they had opened and 
given opportunit}^ for cross-pollination. These were opened and emas- 
culated, after which they were covered with paper bags to prevent the 
access of insects bringing in pollen. When tlie emasculated l)ud had 
matured sufficientl}^ to be receptive, the bag was removed and pollen 
of the variety selected as the male parent was dusted over the pistil. 
The bag was then replaced over the flower and left until fecundation 
had taken place, after which it was removed and the flower labeled. 
The flowers which were used for suppljdng pollen were also covered 
with paper bags previous to their opening, to prevent insects from 
leaving other pollen on them, which might be transferred in the oper- 
ation of hybridization. 

In much of the hj'bridization and breeding work which has been 
carried on .b}^ dift'erent investigators little attention has been given to 
the choice of the varieties used as parents and to the objects sought in 
the experiments. The time of this haphazard work, however, is past, 
as experience has demonstrated that it is far better for the experi- 
menter to have a deflnite object in view and to select, as parents for 
hybridization, varieties which possess the characters that it is desired to 
combine in the hybrid. In the present experiments the following were 
the primary objects sought: (1) Hardier varieties Avhich would endure 
the occasional severe freezes which visit the orange sections, and, if 
possible, varieties sufficiently hardy to be grown farther north than 
the present citrus belt; (2) new fruits having the l90se, easil}" remov- 
able rind of the mandarin and tangerine combined with the quality, 
flavor, and size of the ordinar}^ sweet orange; (3) new fruits having 
the sprightly acid flavor of the pomelo with the bitterness reduced, 
and the loose, easily separable rind of the mandarin and tangerine; 
and, (1) new fruits intermediate between the pomelo and the orange 
which would possess desirable market qualities. 

In all of the writers' experiments these primary objects have been 
kept clearly in view, and varieties have been selected for hybridization 
which by their combination would be likely to give hybrids having 
the characters desired. As the hybrid fruits matured they were sent 
to Washington, where the seeds were extracted and germinated in a 



np:w citrus creations. 223 

greenhouse. When the 3'oung seedlings had reached a size of from 12 
to 18 inches in height th(\v were sent to the Department's Subtropical 
Garden at Miami, Vhx., whore they have since been grown under the 
supervision of Prof. P. H. Rolfs. \\'li('n the seedlings were sent south 
the tops veere cut back and the twigs used to furnish budwood for 
budding proper stocks to <)l)tain trees for trial. These trees were 
tested in cooperation with different growers, arrangements being 
made with a number of intelligent, trustworthy growers to bud from 
one to two stocks with each of these hybrids and grow them until 
sufficient fruits had been produced to show their character and value. 
In the case of the hybrids made with the idea of securing hardiness, trees 
were budded and grown under the direct supervision of the Depart- 
ment by ]\Ir. G. L. Taber, at Glen St. Mary, in northern Florida. 
Owing to the conditions under which the various trees have been grown 
very few of them have yet fruited. Several freezes have visited Florida 
in the last five years, and in man}^ instances all of the h3^brid buds sent 
to growlers have been killed. In l>ut few instances have large stocks 
been used which would force the ))uds into earh' bearing; nevertheless, 
several very promising new t3^pes have been produced, and without 
doubt many more fruits of value will be obtained when all of the 
hybrids have been brought into bearing. It should be noted that in 
fruit trees of this sort all of the varieties are clo?is, that is, varieties 
which are propagated by buds, grafts, or cuttings. A hybrid of value, 
when once secured, can thus be propagated indetinitely by budding or 
grafting, without awaiting fixation, as is necessary' in the case of plants 
propagated by seed, where a desirable hybrid nuist be selected through 
a numJjer of generations and bred to a lixed type that will come true 
through the seed before it can l)c utilized. 

Production of Hardy Citrus Fruits. 

The citrus industry in Florida has frequently suffered from severe 
freezes. The most disastrous of these probably were the freezes of 
1835, 1886, and 1891:-95, which killed or seriousl}' injured almost every 
tree in the State. Other minor freezes have occurred from time -to 
time, which, while not so severe, have serioush' damaged man}- orange 
groves. In California and Arizona, also, citrus trees arc frequentlj' 
injured by severe cold. It is thus clear that the most desirable improve- 
ment in the orange and other citrus fruits is the securing of varieties 
which can endure lower degrees of temperature and which may be grown 
throughout the present orange-producing sections without danger of 
injury by cold. 

In attempting to improve citrus fruits in hardiness, two methods 
present tiiemselves. .One method would be to grow a large number 
of seedlings and select from them the individuals which possess the 



22-1 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 

greatest degree of hardiness, and continue this selection throughout 
numerous generations in the hope of augmenting any greater degree 
of hardiness that might be discovered. To pursue this polic}^ with 
citrus fruits would require so long a period to secure a.nj marked 
results that the method is impracticable. This is shown by the 
fact that for manj'^ years citrus growers have been making selec- 
tions based on the hardiness of seedlings, and as 3^et no appreciable 
advance has been made in this direction. 

A second method would be to select some hardy wild or cultivated 
type and cross this with the sweet orange or lemon in the hope of 
obtaining good varieties, combining the hardiness of one with the good 
fruit quality of the other. If such a hardy type exists, this method 
would certainly seem to be the quickest and most practicable way of 
securing hardy varieties. A species of citrus known as the trifoliate 
orange ( Citrus trifoliatd) is such a hardy tj^pe, which can be grown 
without protection as far north as Philadelphia. The common variety 
of the trifoliate orange (PI. X) was introduced into this countrj' by the 
late William Saunders, of the Department of Agriculture, in 1869. The 
tree is small and bushj^ and very spiny, and the leaves are trifoliolate 
and deciduous. It is quite commonly grown as a lawn tree in the 
North and as a hedge plant in the South, while in the colder sections 
of Florida it is used as a hardy stock on which to bud the common 
orange and other citrus fruits. The fruit (PI. XII, fig. 4, and PI. XIII, 
fig. 2) is round and small, ranging from li to 2 inches in diameter, and 
is orange -colored. The surface is covered with minute fuzzy hairs and 
is in most cases smooth, being rough only in the larger and more vigor- 
ous specimens. The rind, which adheres tightly, is about one-sixteenth 
inch in thickness. The pulp is acrid, bitter, and gummy, and the 
enormous number of seeds leave little room for pulp. The fruit is 
thus worthless as far as edible qualities are concerned. It is highly 
' aromatic and attractive in appearance, making the plant desirable 
for ornamental purposes. Unfortunately, however, for its use in the 
South, the tree is deciduous, losing its leaves in the fall, and in gen- 
eral throughout this section an evergreen hedge is most desired. Not- 
withstanding this, it is generally cultivated as a hedge plant because 
of other qualities which make it desirable for this purpose. Its hardy 
character, however, is the factor of importance in connection with the 
experiments in the production of a hardy orange. 

A second variety of the trifoliate orange, having rather larger 
leaves and very large flowers, has been found growing in several 
places in Washington, D. C, but has not been used in the present 
experiments. 

The first variety described, the ordinary trifoliate orange, was the 
one used in the work of the writers, though the second might be more 
promising to use with the lemon, and some of these crosses have been 



Yearbook U. S. Dept. of Agnculture, 1904. 



Plate X. 




Branch of Trifoliate Orange. 
[.\l){)Ut oiK'-lmlf iiiitnnil si/e.] 



NEW ( ITKUS CREATIONS. 225 

iiiiido. However, no fruits have thus far been obtained. All varieties 
of tlie trifoliate group are deciduous, and ripen their fruit early in 
the fall before frost. They are also late in blooming in the spring, the 
flowers, which appear before the foliage, not even showing until the 
common sweet orange is nearly through ])looming. The ti'ifoliate is 
thus al)out two to three weeks later to start growth in the spring, and 
is never caught by late frosts. The early ripening of the fruit in the 
fall, moreover, allows the tree to become dormant at a time much 
earlier than the connnon sweet orange, which is evergreen and inclined 
to grow more or less through the winter during warm periods. 

It is a Avell-known principle in plant breeding that in hybridization 
tlie characters of races and species break up and become cond)ined in 
different waj's in the hybrids. It would thus seem entirely pro))able 
that by crossing and recrossing the common orange with the hardy 
trifoliate orange a hybrid could ultimatelv be obtained combining the 
desirable fruit characters of the former with the hardiness of the latter. 
Many instances are recorded where hybrids have been obtained com- 
bining certain characters of the parents, and a few cases are known of 
hybrids which are intermediate in character of hardiness between the 
j)arents. ])eing more tender than one parent and much hardier than the 
other. The impro])abiIity of o))tainingthe hardy (luality in an orange 
variety is thus not so great as one might be inclined to think. If, by 
infusing the blood of the trifoliate orange into the sweet orange, we can 
modify the season of growth of the latter and cause it to remain more 
dormant during the winter i«id later into the spring, our ol)ject would be 
accomplished. If, on the other hand, a hybi-id can l)e secured having an 
entire segregation of the characters and combining the hardiness of the 
trifoliate with the superior fruit qualities of the sweet orange, a far 
greater success would be achieved. 

The sweet orange and the trifoliate orange are very distinct in chai- 
acter, and it has been found in the course of the experiments that they 
are ver}' difficult to hybridize. Even by using the utmost care in the 
process of hybridization only about 2 per cent of the flowers operated 
upon set fruit. The process of crossing flowers of the trifoliate orange 
with pollen of the ordinar}' orange is nuich more difficult than the 
opposite cross where the orange is used as the female, as the flowers of 
the trifoliate orange are quite small at tln^ time of emasculation, are 
attached very lightl}', and are easily ])roken off or injured. It would 
thus seem that the lack of success in getting fruits to set was caused 
partiall}' by the injury to the flower in the process of emasculation. 
This, however, is certainly not the oid\' reason for the small percentage 
of fruits that set, as there is also a great loss when the reciprocal cross 
is made; that is, when the common orange is used as the mother parent. 
The seeds resulting frdm these crosses were also poor in germinativc 
30536—05 2 



226 



YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 



power, not more than half of the seeds obtained finally producing seed- 
ling's. In the course of the experiments, however, a number of h3"brids 
were secured where both the common oi-ange and the trifoliate were 
used as the seed-bearing parent. Some of these hj^brids plain h' show 
the characteristics of l)oth parents and are doubtless true hybrids. Out 
of 40 hybrids of the trifoliate orange crossed with the pollen of the sweet 
orange, 29 resembled the former in habit and foliage characters, so 
far as could be observed, while 11 were clearly intermediate in these 
characters. These 11 intermediate plants are YGvy similar to each other, 
deriving certain characters from each parent. 
The leaves are trifoliolate in form and are nuich 
larger in general than those of the normal tri- 
foliate orange. The central leaflet has a ten- 
dency to be much larger, but the lateral leaflets 
remain about the size of those in the trifoliate 
orange, and in some of the seedlings these lat- 
eral leaflets tend to become abortive, thus 
approximating the unifoliolate SAveet orange. 

During these experiments it has been found 
that some complexity is liable to arise, owing 
to the polyembryonic nature of citrus fruits. 
It is well known that seeds of various citrus 
fruits frequently produce more than one seed- 
ling. Instances have been noted where a single 
seed has produced a;? many as 13 seedlings. In 
cases where strikingly distinct types of citrus 
fruits were crossed, the interesting observation 
was made that where two or three seedlings 
were developed from a single seed they not 
infrequently showed marked foliage differences 
(lig. 12). Strasburger, in his critical study of 




Fig. 12.— Thr 



from 

(tangerine crossed with trifoli- 
ate) ; seedling with trifoliolate 
leaves (on the right) is a true 
hybrid; the other two seed- 
lings with tangerine-like 
leaves are false hybrids. 



a single seed of a hybrid the polycmbryouy of this group, found that the 



embryos, other than those developed from the 
fecundated egg cell, are derived from certain 
cells of the nucellus, lying near the embryo 
sac wall, which become specialized, grow, and 
develop rapidly, and form a tissue mass, which pushes out into the 
embryo sac and forms an embryo similar to that formed in the noi-mal 
way from the egg cell. The embryos formed in this way Strasburger 
called "adventive." If we correctly understand the action of fecun- 
dation, it is clear that in this group only those embryos that develop from 
the egg cell proper as a result of the fecundation would show an indi- 
cation of hybridization. Since the adventive embryos develop directly 
from the mother tissue, in these we should not expect to see any of 
the characters of the male parent. This conclusion was reached by 



NKW flTRUS CREATIONS. 227 

the writers early in tlio oxporiinoiits, Ix'foro the growilig of the .sood- 
liii<>N had shown d(^tiiiitoly what would tako ])lact>, and the dcvolopiuent 
of the hybrids has proved this conclusion to Ix' well founded. In sev- 
eral hybrids of the sweet orange, which is unifoliolat(% with the trifoli- 
ate oi-ange, which has trifoliolate leaves, where the former was used 
as the female parent, two aiul tiiree seedlings have been produced frour 
the same seed, one of which had trifoliolate leaves, showing clearly the 
influence of the male pariMit, while the other oi- others had strictly 
unifoliolate leaves exactly like the mother parent. It is certain in such 
cases that the trifoliolate seedling inherits this character from the male 
parent, and that the embryo from which it grew was devel()[)ed from 
the vgg cell proper. The other seedlings in such cases which have 
unifoliolate leaves were doubtless developed from the so-called adven- 
ti\'C embryos. The same phenomenon has also l)een o))served where 
the trifoliate orange was crossed with pollen of the common orange 
and also in hybrids of the tangerine orange crossed with the common 
orange (lig. 1'2). The ol)servations have been suffici«Mit to establish its 
common occurrence in citrus hybridization. Attention was called to 
this phenomenon by one of the writers" in February, IJJOO. 

In hybridizing citrus fruits to secure improved sorts this eti'ect 
unfortunately causes serious complications. In man^' cases citrus 
hybrids resemble the female parent in foliage characters, or the parents 
differ so little in their foliage characters that the hybrid can not be 
clearly distinguished, and it may thus ))e seen that until the seedlings 
fruit it is impossible to determine whether they are true hybrids or 
simply false hyl)rids developed from adventive embryos. It will 
thus be iuiavoidal)le in such work to grow many si'edlings which come 
from adventi\e embryos and which are not true hyl)rids. Such false 
hybrids ordinarily would not be expected to give valuable varieties, 
and growing them greatly adds to the trouble and expense. 

The increase in vigor which is comnionly exhibited by hybrids 
between distinct parents is clearly shown l)y hyltrids between the trifoli- 
ate and the common orange. Those which have intermediate charac- 
ters, showing that they are true hybrids, are almost invarial)ly much 
more vigorous than th(> se(Hllings of either parent. The hybrids which 
exhibit no intermediate ciiiiriu'ters and are probsibly developed from 
adventive embryos, do not exhibit this increased vigor. Illustrations 
of this increase in vigor will l)e given later, 

THK C'lTKANCK, A NkW (iKOUP OF C'lTKUS FrUITS. 

In the cours(> of these exi)eriments two fruits have been produced 
which are hybrids between the common sweet orange and the trifoliate 
orange, and whicii promise to be of considerable value. They lie 

« Webber, H. J., Conipfications in CitruH tlybricfization (-aused by Polyembryony. 
Science, n. s., 11:H08, February 2'A, 1!»00. 



228 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 

about midway between the two parents, but are not sweet oranges, 
trifoliate oranges, nor lemons, and are totally different from any 
other group of citrus fruits. It therefore becomes necessary to refer 
these hybrids to a new group of citrus fruits, and it is proposed to 
call them "citranges," a term made up of the first sj^llable of the word 
citrus and the last S3'llable of the word orange. The two varieties 
which are to be referred to this group are described in detail below. 

KUSK CITEANGE. 

[PLATES XI ^ND XII, AND PLATE XIII, FIGURE 1.] 

Name and origin. — The Rusk citrange originated as a hybrid 
between the common orange (used as the female parent) and trifoliate 
orange (used as the male parent). The trees are far more hardy than 
the common orange, and produce a fruit intermediate in qualities 
between the two parents. This being the first hard}" orange or 
citrange produced, and belonging to an entirely new group of citrus 
fruits which will doubtless become of v'ery great importance in 
many parts of the world and be improved in a marked degree, has been 
named the Rusl\ in honor of the first Secretary of Agi-iculture, Hon. 
J. M. Rusk, under whose administration the first work on citrus fruits 
in Florida was undertaken by the Department of Agriculture." 

The Rusk citrange was one of three seedlings grown from a single 
h^^brid fruit which developed in the grove of Col. G. H. Norton, at 
Eustis, Fla. , in 1897. Two of the seedlings, from which several budded 
trees have been grown, resemble the ordinary sweet orange in foliage 
and general character, and are apparently false hj^brids from seeds of 
adventivCj polyembryonic embryos, which, as explained above, are 
developed from certain cells of the mother tissue without the inter- 
vention of the male element. These two seedlings have unifoliolate 
leaves, and are evergreen like the common orange, and while the}' 
have not 3^et fruited, owing to the fact that they have been sev- 
eral times frozen back, it is not expected that they will produce 
anj'thing of value, nor, judging from a test already made, will they 
produce hardier types. The other seedling. No. 716, was a strictly 
intermediate type, having trifoliolate leaves similar to the male 
parent, though rather larger (PI. XI). Even the first leaves of the 
3'Oung seedling exhibited this character, and a photograph of a seed- 
ling but slightl}^ over 1 inch high published b}" the writers at that 
time plainh' shows this trifoliolate character.^ No. 716 was further- 
more much larger and more vigorous than the other two seedlings, 

«In the Cosmopolitan Magazine for July, 1904, Mr. H. Gilson Gardner referred 
to this citrange as the Webber, but the writers suggest, with the approval of the- 
Secretary of Agriculture, that it be known as the Rusk. 

& Swingle and Webber, Hybrids and their Utilization in Plant Breeding, Yearbook 
of the Department of Agriculture for 1897, p. 400, fig. 13. 



Yearbook U. S. Dept. of Agriculture, 1904 



Plate XI. 




Hybrid Seedlings of Common Orange (Female Parent^ and Trifoliate Orange 

(Male Parenti. 

[N.I. TIC, (.,1, riKht). Rusk citranso; Nos. 7U and 7I.\ .seedli.iKs from iIr. same fruit as .\„. Tic, 

hut resembling the mother parent.] 



Yearbook U. S Oapt. of Agriculture, igO*. 



PLATE XII. 







3>y?cu 




▼ 




iJ ScdiJt 




MOEH A CO . B«\.TIMOnt 



pRulib ui- (nu;:.h. <^iii\amGE AND TRIhULiAit UmANGE. Naiuk/xl biZt. 

Fig. 1— Rusk Citranqe, in an early stage of maturity. Fig. 2— Rusk Citrange, fully mature 

Fiq. 3— RUSK Citrange, cross-section of mature fruit, fig. 4— trifoliate orange. 



Yearbook U. S Dept. of Agriculture, 1904. 



Plate XI 



= O 








NEW riTRT^S CREATIONS. 229 

showing an incroasi' in vigor, whith i.s sucli a marked character of 
hyhrids in general. Trees were budded with these h3'brids in the 
spring of 1899, in the nurser}' of Mr. G. L. Tal)(>r. at Gh^n St. Mar}', 
Fhi. Tiie lirst fruits were received in September, 1902, one tree that 
season l)earing about a dozen fruits. In the fall of 1903 the same 
tree produced about a bushel of fruits, and several other ti'ees, l)udded 
on trifoliate-orange stock, gave about a half-dozen fruits each. A 
similar number was also produced in 1904. There have thus been pro- 
duced sufficient fruits to afford a fairl}' thorough test of this hybrid. 

Description of friit and tree. — Fruit compressed-spherical or nearly round; 
small, U to 2 inches in diameter, 1} to 1| inches high; color, when fully mature, 
deep orange, with reddish flush of cadmium orange at apex; surface smooth and 
glossy, with a few scanty hairs visible under niagnitication; very heavy, freciuently 
sinking in water; calyx persistent, green, rather larger than that of the ordinary 
orange; skin adhering very close to the fruit, thin, -/_, to J incii tliiek, tender; oil 
glands small and round; i)ulp tender, melting, exceptionally juicy (lig. 13); color 
orange yellow; pulp cells small, similar in shape to those of ordinary orange; seg- 
ments, 10; membranes thin and tender, thus making very little rag; axis small, 
J to /,. inch in diameter; flavor sprightly acid and slightly bitter; nearly seedless, 
averaging one seed to two fruits; aroma strong and ])lcasant, a combination of that 
of tiie sweet orange and the trifoliate orange. Tree similar in shape to trifoliate 
orange, vigorous and hardy, evergreen or semi-evergreen, tall and shapely; foliage 
dense, leaves trifoliolate and larger than those of ordinary trifoliate orange. Season 
of maturity very early, from Sej)tendjer 1 to November 1. 

The fruit of the Husk is a beautiful little orange of excellent texture 
and exceedingly juic}'. It is rather too sour to be eaten out of hand, but 
with sugar is very palatable. The bitterness is no more pronounced 
than in the grape fruit, and the aroma, which is derived largel}' from 
the trifoliate orange, is very strong and pleasant. The fruit of the 
Rusk may be utilized for making citrangeade, similar to lemonade or 
limeade, or ma}' be eaten with sugar as a breakfast fruit. It also 
makes excellent pies, preserves, and marmalade, and may bo used for 
general culinary purposes. 

WILLirS ("ITHANOE. 

[PLATK XIII, FIGURE ;',. PLATE XIV (777), AND PLATE XVL] 

Name and origin. — The second citrange which has given evidence 
of value has resulted from a hybrid of trifoliate orange with pollen 
of the common orange, being thus what is known as a reciprocal 
hybrid of the Rusk citrange. In general it possesses characters inter- 
mediate l)etween the two parental varieties, and is similar to the Rusk 
in tree and fruit characters, yet differing considerably in detail, so that 
there is no trouble in clearly distinguishing it from the Rusk citrange." 

aThis citrange the writers propose, with the approval of the Secretary of Agricul- 
ture, to call the Willilf!. In the Cosmopolitan Magazine for July, U>04, Mr. (iardner 
called this citrange the SwuKjlr, but the writers would prefer that it be known as the 
PTiWita, in honor of the First Assistant Secretary of Agri<-ulture, lion. Kdwiu Willits. 



280 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 

The Willits citrange was one of 40 seedlings from a single hybrid 
fruit grown and developed in the grove of the late Col. G. H. Norton, 
at Eustis, Fla. Of the 40 hybrids of this series 11 exhibited char- 
acters clearl}^ intermediate between the two parents, being evergreen 
and having trifoliolate leaves much larger than those of the trifoliate 
orange (PI. XIV). The remaining 29 seedlings are all deciduous and 
have leaves apparently like the tj'pical trifoliate orange. Eighteen of 
these have fruited and all produced fruits indistinguishable from the 
trifoliate orange. It would thus seem clear that the 29 which resem- 
ble the trifoliate parent are false hj^brids, having developed from 
adventive embryos, as already explained. Four of the apparently 
intermediate seedlings have fruited, and all have given fruits clearly 
partaking of the nature of both parents. These are, therefore, cer- 
tainly true hybrids. 

All of the h3'brids of this series which show intermediate characters 
are exceptionally vigorous, showing in this regard also their true 
hybrid nature. The smallest of them was as large as the largest of 
the seedlings which exhibited no intermediate characters. The vigor 
of the young hj'brid seedlings in comparison with both parents and 
the comparative size of leaves is shown in Plate XV. Here No. 845, 
a cross of two typical oranges and one of the largest of 500 seedling 
oranges of similar kind, is 3'et far smaller than the medium-sized true 
hybi-id No. 772. No. 780, one of the largest of the 29 false h3^brids, 
affords a comparison of the size of the true h3'brids with the t3'pe of 
the mother parent. The true h3'brid No. 772, used here for com- 
parison, is not the largest of the hybrids secured, but is of medium 
.size. The h3'brids between distinct species and races are ordinarily 
intermediate between the two parents and mainly very uniform, so 
that the hybrids of the lirst generation usuall3' resemble each other 
ver3' closel3\ In the case of the h3^brids between the trifoliate orange 
and the common orange, however, the seedlings have been found to 
differ from each other verv markedly. The fruits of all of those 
which have thus far come into bearing are essentialh^ distinct in 
flavor, size, and appearance. Tlie seedlings also differ in tree and 
foliage characters. They are all similar, however, in having fruits 
iiearl3^ intermediate in size, with some of the bitter flavor of the tri- 
foliate fruit, and in having trifoliolate leaves and semi-evergreen 
foliage. The difference in foliage characters of some of these hybrids 
and their parents is shown in Plates XIV and XV. 

Description of fruit and tree. — Fruit compressed -spherical, or nearly round; 
small, from 1 1 to- 2 1 inches in diameter (PI. XIII, fig. 3, and PI. XVI), and from 1^ 
to 2 inches in height; color from cadmium yellow to orange; surface rough with deep 
depressions over the largest oil glands, and with more or less pronounced furrows or 
ridges running from base to apex; weight medium, about the same as water or 
somewhat lighter; calyx persistent, with large and fleshy lobes; rind thin, J inch in 



Yeaibook U. S. Dept. of Agriculture, 1904 



Plate XIV 



»*•» 




33 




3*2 


^ 


31 


^^/C- 


30 


NT 


29 


x- T/»- 


a? 


ll^ 


27 


^ 


26 


V 




Seedling Hybrids of Trifoliate Orange Crossed with Pollen of the Common 

Orange. 
[No 776 IV false hvbri.l, sliowinj,' no intemiediale churacters and having small .lofiduous leaves: 
No 777, seedling of Willits citranKe. showing the evergreen foliage and other nitermediate 
characters: Nos. 77S and 779, two seedlings grown from the same seed. No. 779 (on the right), 
showing intermediate characters. No. 778 (on the left), showing only the normal characters of 
the Irifoliate orange.] 



Yearbook U. S. Dept. of Agriculture, 1904. 



Plate XV. 




Seedlings of Citrus Hybrids, Showing Relative Vigor of True and False 

Hybrids. 

[No. 780. a false hybrid (trifoliate x swei't orange); No. 772, a true intermediate hybrid (trifoliate x 
sweet (iraiifie), with large trifoliolate leaves; No. 845, a eross of two ordinary orange varieties. 
All seedlings of .same age.] 



Yearbook U.S,Oept.o.AgMCultur.M 904. 



PLATE XVI. 





'i>69a 



aA^>^^(y^<^ 



HOV * CO , B»l.TlMORt 



WlLLITS CiTRANGE. NATURAL SIZE. 



NKW CITUrs CKKATIONS. 231 

thii'knesH, and triKlor, not adlu'rinjj jjo closf to fniit as in tlie Rusk citrange; pulp 
translucent, light lemon yellow, re.-enihling the onlinaiy lemon; Hegments 6 to 10, 
separated hy thin tender membranes; texture of fruit very tender, being ecpial to 
that of the best lemon; axis small, about J ineh in diameter; flavor sprightly aeitl, 
similar to lemon, with very slight l)itter taste of trifoliate orange; nearly seedless, 
averaging about one seed to four fruits; aroma mild and pleasant, combining the 
aromatic resinous odor of the trifoliate orange with the very delicate odor of the 
eommon orange. Trees similar to trifoliate orange, vigorous and hardy, evergreen 
or semi-evergreen, medium height and shapely; foliage dense, leaves trifoliolate and 
larger than those of the ordinary trifoliate orange (PI. XIV); season of maturity very 
early, from September to the last of November. 

The Willits citrange makes a beautiful, vigorous-oiowino- tiee and 
gives evidence of l)eino- of value as a decorative or lawn tree. The fruit 
makes a tine drink similar to lemonade or limeade and will he found 
pleasant as an acid fruit to eat witii sugar. It is an excellent ."substitute 
for the lemon to serve with fish or 03^sters and is valuable also for culi- 
nary pui'iwses, for which its seedlessness renders it specially desirable. 
The products made from the Willits citrange are very diti'erent in 
flavor from those made from the Rusk citrange. Thej' possess more 
nearly the charactcn- and flavor of those made from the lemon. 

HOW UAI!I)V IS THK CITRANGE? 

All of the diti'erent citrange seedlings were budded on trifoliate 
orange stocks at Glen St. Mar}', in northern Florida, in the spring of 
1899. In January of 1900, when the i)uds were about 8 months old, 
a severe freeze occurred in which the temperature went down to about 
15^' or 18^ F. Mr. Taber recorded a temperature of 18" above zero at 
Glen St. Mary. At Macclenny, Fla., 3 miles east of Glen St. Mary, 
a minimum temperature of 15° was recorded, while at Lake City, 
about 20 miles west, the minimum temperature recorded was 17° F., 
the record at Macclenny and Lake City being made b}'^ voluntary 
observers of the United States Weather Bureau with speciall}' corrected 
instruments. After this freeze a report from Mr. Talker stated that 
the foliage on the buds of Rusk (No. 716) and Willits (No. 777) 
citranges still remained gi'een on the tree, and that the tops w^ere 
apparently entirely uninjured. All of the hybrids between the tri- 
foliate orange and the coimnon orange which show intermediate char- 
acters also remained uninjured and retained their foliage fresh and 
green, with the exception of an occasional twig which at the time of 
the freeze was soft and immature. 

In this freeze ordinary oranges suffered severely, large buds in 
many parts of the Sbite l)eing frozen to the groimd, and this was the 
ca.se with ordinary oi'ange buds growing immediately beside the 
citranges at (ilen St. •Mary. Although no freeze which has occurred 
since has l)een so severe, temperatures of from 20° to 23 have been 



232 YEAKBOOK OF THE DEPARTMENT OF AGRICULTURE. 

several times recorded. In none of these freezes have the citranges 
been injured, although buds of ordinar}^ oranges have frequently been 
severely damaged. 

Aside from the tests made at Glen St. Mary, Fla., sets of the h3'brids 
which had been made with the idea of producing hardy varieties were 
sent- to the Florida, Georgia, South Carolina, Alabama, and Louisiana 
experiment stations to be grown and tested in cooperation with the 
Department of Agriculture. These were planted in March, 1900. At 
the experiment station at Lake City, Fla., which is in about the same 
latitude as Glen St. Mary, the trees have passed through the winters 
since March of 1900 without serious injury. Here the trees have 
been grown under the direction of Prof. H. Harold Hume, who 
reports that the temperature has several times fallen to a point where 
all ordinary orange trees were severelj^ injured or killed without 
resulting in injury to the Rusk or Willits citranges or to the other 
hybrids of intermediate nature. Professor Hume reports that the 
minimum temperature recorded during this period was 21° in Decem- 
ber of 1901. 

At the Georgia experiment station a set of the trees has been tested 
under the supervision of Director R. J. Redding and Prof. H. N. 
Starnes. At this place the temperature fell in Februar}", 1901, to 17° F. 
above zero, and in December, 1901, to 8°. The majority of the inter- 
mediate h3^brids passed through these freezes without serious injur3^ 
The Rusk citrangc was killed back to some extent, but lived through, 
and is now reported to be in good condition. The trees of the Willits 
citrange planted at this station have died, but whether directly from 
the effects of the cold is not certain. 

At the Alabama experiment station, Auburn, Ala., a set of the 
trees has been grown under the supervision of Professors Earle and 
Mackintosh. At Opelika, Ala,, about 10 miles distant, the lowest 
temperature recorded, since the trees were planted, was 9° F. above 
zero in December, 1901. Trees of the Willits have remained uninjured, 
while trees of the Rusk citrange are all reported as dead. Here again, 
however, it is not clear from the records whether they died as a result 
of injury from freezing, although this might be assumed. However, 
almost all of the strictl}' intermediate hybrids hiave survived the winters 
at this place without serious injur3\ 

At the South Carolina experiment station, Clemson College, S. C, 
a number of the hvbrid trees have been grown and tested under the 
supervision of Prof. C.C. Newman. Unfortunately a complete set 
of the hj^brids was not sent to all of the cooperating stations, owing 
to a lack of trees of certain numbers. It happened that neither the 
Rusk nor the Willits citrange was among the number sent to the 
South Carolina station. However, a number of the intermediate 



NEW CITRUS CREATIONS. 233 

livbrids similar to the Rusk and Willits citranges have been grown 
and tested at this station, and have passed through the winters 
since March, 1900, without serious injury. At this station they liave 
endured a mininumi temperature of G^ F. above zero, which occurred 
in December, 1901. 

At the Louisiana experiment station a set of the h3')jrids, among 
them the Rusk and Willits citranges, have been tested under the innuedi- 
ate supervision of Dr. W. C Stubbs. At this station the temperature 
in December, 1901, fell to 21^^ F. above zero, and remained ])elow 2(P 
above zero for nearh' a week. All of the h3^brids survived the freez- 
ing without serious injury, although trees of the ordinary orange in the 
vicinity were in many cases killed. 

It will be noticed from the above tests that both the Rusk and the Wil- 
lits citranges are nuich hardier than ordinary oranges. While the 
Rusk citrange endured the freeze of December, 1901, at Experiment, 
Ga., it was killed, or at least died, at Auburn, Ala. On the other 
hand, the Willits citrange died at the Georgia experiment station 
and survived at the Alabama experiment station. It is well known 
that the condition of a tree at the time a freeze occurs has a great 
deal to do with its hardiness. Trees which endure the most severe 
winters at the latitude of Washington, D. C, have been killed in some 
of the freezes in Florida, owing to the fact that they were in a sappy, 
growing condition at the time the freeze occurred. That some of these 
citrange trees were killed, therefore, at certain stations does not indi- 
cate that thev are tender. The fact that the}' have survived the same 
degree of cold at other stations indicates that they would have sur- 
vived in all cases had they been in a properly dormant condition. It 
is believed from the evidence now accunuilated that these two cit- 
ranges ma}' be grown without protection throughout South Carolina, 
Georgia, Alabama, Mississippi, Louisiana, Arkansas, and parts of Ten- 
nessee and Texas. It is also pro})able that the}' can be grown in parts 
of Washington and Oregon, and in northern California, which are only 
slightly too cold for the orange, and in certain irrigated regions of low 
altitude in Arizona and possibly New Mexico. It will be remembered 
that the peach tree, which is considered to he fairly hardy, sutlered very 
severely in Georgia in the freeze of December, 1901, to which these 
citranges were exposed. Large peach trees were frozen to the ground, 
and the damage to the peach industry was very great. The range of 
latitude at which the citrange may be safely grown has not been fully 
determined, but it is believed that they will succeed in any of the 
aboA'e-named places where the altitude is not too high. 



234 



YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 



OF WHAT VALUE IS THE CITRANGE? 

The fruits of the citranges thus far produced are small, acid, and 
bitter, and from the standpoint of the ordinary orange grower would 
be considered practically worthless. This opinion, however, would be 
based entirely on a comparison of the citranges with oranges of fine 
quality such as are produced in Florida and California. When it is 
considered that these fruits can be grown through the Gulf and South 
Atlantic States without protection, where there is now a dearth of 
acid fruits, their great value can be understood. Both the Rusk 
and the Willits citranges make a refreshing '* citrangeade," similar 
to lemonade and limeade. It is also very similar to the orangeade 





Fig. 13. — Rusk citrange (on left) and lemon (on right), showing comparative amount of juice from 
fruits of same volume. (Five-eighths natural size.) 

made from the native sour oranges of Florida. The citrangeade has 
been tested by a large number of people, and all who have made a 
comparison pronounce it fully equal to lemonade or limeade, while 
some think it superior. The fruits are exceptionally juicy, the Rusk 
citrange in particular giying a much larger proportion of juice than 
the best lemons on the market (tig. 13). The fruits make excellent 
pies and marmalade, and for this purpose they are probably equal 
to the orange or lemon. Fortunately, the pies and marmalade 
made from the two fruits are of distinctly different qualit}^ and both 
differ again from the lemon in this respect. The Rusk citrange 



NEW CITRUS CREATIONS. 235 

has also been found to nmko un oxcolloiit i)re.servo. The fruits will 
probably prove valuable for jrenoral culinary purposes in the making- 
and tlavoring- of oakos. for use in niakino- jellies whore lemons are 
now employed, and probably in many other waN's. While they are 
too acid to eat out of the hand they will be found very palatable to any- 
one enjoyinj^: an acid fruit, especially when eaten with sugar. The 
citrange will prol)ably prove of vahu? mainly as a home fruit for culti- 
vation throughout the Southern States mentioned above, where the 
sweet orange, the lemon, and the lime can not be grown, A few trees 
should be cultivated in every yard in this section. The trees are 
attractive in shape and semi -evergreen, so that they will make desirable 
lawn trees. Wherever a home can be supplied with them, it will be 
possible on the warm days between the 1st of September and the 1st 
of November to pick a few fruits and make a desirable, refreshing- 
beverage. It is believed that they will prove a decided ])oon to a very 
large section of the country. While the fruits already obtained present 
results far-reaching and important, even more striking and valuable 
results will doubtless be obtained when seed from these fruits can be 
grown and selections of the best citranges made from among their 
progen}'. These two citranges, it is confidently believed, will be the 
progenitors of a large and numerous group of hardy, edible fruits. 

The Tangelo, a New Groui' of Loose-Skinned Citrus Fruits. 

During the course of these experiments a hybrid has been produced 
between the pomelo and tangerine which occupies a position interme- 
diate between these two well-known fruits. It is neither a pomelo 
nor a tangerine, but is different and unique and bids fair to take a 
place by itself. The fruit is intermediate in size between the two 
parental varieties, has the easily removable rind of the tangerine, and 
in flavor is somewhat sweeter than the pomelo, with less bitterness. 
It is distinct from any of the various groups of citrus fruits and 
should, therefore, be referred to a new group. The term "'tangelo*' 
is suggested by the writers as a name for this group of loose-skinned 
fruits, which lie midway between the pomelo and tangerine, the word 
being a coml)ination of the tirst syllable of the word t(i)i</erh>i', with 
the ending of the word potne/o. A variety of citrus fruits known as 
the '' nocatee,"' which has already been described and introduced, is 
apparently somewhat similar to this fruit and is evidently a hybrid 
between the tang-erine and pomelo. This and the new Sampson tan- 
gelo which is described below, are at present the only two varieties 
that can be referred to the tangelo group. 



236 YEARBOOK OF THE DEPAETMENT OF AGRICULTURE. 

THE SAMPSON TANGELO. 

[PLATES XVII, XVIir, AND XIX.] 

Name and origin. — The Sampson tangelo is a hybrid between the 
ordinary pomelo (female parent) and the Dancey tangerine (male 
parent). The fruit from which the seedlings came was from a cross 
made in the grove of Mr. Frank Savage, at Eustis, Fla. The hybrid 
fruit contained a very large number of seeds, 76 in all, which gave a 
total of 106 seedlings, several of the seeds having produced more than 
one seedling. A large majorit}^ of these seedlings have not yet fruited, 
but of those that have borne fruit all have the appearance of pure 
pomelo, except No. 1316, which exhibits characters plainlj- interme- 
diate between the pomelo and the tangerine, being about midway 
between the two in size and other characteristics. The color of the 
fruit is darker orange than the pomelo, though not so red as the tan- 
gerine, and the color of the pulp is more nearly like the tangerine 
than any of the varieties of the pomelo. In flavor it is sprightly acid, 
but rather sweeter than the pomelo, and it has a slightly bitter taste 
derived from that parent. Its most pronounced characters, however, 
are the looseness of the rind and the ease with which the segments can 
be separated; in these qualities it partakes of the nature of the tan- 
gerine. The fruit may be described as a small " kid-glove'' pomelo. 

The hybrid seedling from which this variet}^ developed was grown 
and fruited by Mr. F. G. Sampson, of Boardman, Fla., who since the 
beginning of the citrus experiments of the Department has given 
material aid in man}^ ways. The writers therefore take pleasure in 
suggesting for this new tangelo the name of Sampson, in recognition 
of his aid in connection with the experiments. 

Of the 106 seedlings of the series from which the kSampson origi- 
nated, 5 have leaves with narrow, winged petioles, the foliage resem- 
bling more closely the tangerine than the pomelo. The only one of 
these that has thus far fruited is No. 1316, the Sampson, which, as 
indicated above, in fruit characters clearly exhibits its true hybrid 
nature. The other 101 seedlings have foliage which would be classed 
as purely pomelo in character. Only 6 of these have thus far borne 
fruit, and all of the fruits produced resembled pure pomelo. From 
these observations it would seem that only the 5 seedlings having 
tangerine-like foliage are in reality true hybrids. The others are 
probably false hybrids, developed from adventive embryos. 

Description of fruit and tree. — Fruit compressed-spherical, slightly drawa 
out at stem end like tangerine; of medium size, averaging 2^ inches in diameter 
and about 2| inches in height; weight from 163 to 248 grams; calyx persistent as in 
common orange; color chrome yellow, considerably darker than the pomelo, though 
not so red as the tangerine; specific gravity about the same as water; skin thin, about 
one-eighth of an inch in thickness, loose and easily removable, like the skin of the 



Yearbook U. 5. Dept. of Agripulturo, 1904. 





"PSTa 



ad^fi^o'X^ 



HOex 4 CO , ■«LTIMOIIC 



Sampson Tangelo. Natural size. 



Yearbook U. S. Dept. of Agriculture, 1904 



Plate XVIII 




<^ 




\ 




Sampson Tangelo, Showing Easily Removable Rind. 
IN.itviral sizf.l 



Yearbook U. S. Dept. of Agricul-.ure, 1904. 



Plate XIX. 





Sampson Tanqelo Above; Ordinary Pomelo Below. 
[Niituriil size.] 



NEW CITRUS CREATIONS. 237 

tangerine; surface pmooth and glossy; oil glands large and conspicuous, rendering the 
rind translucent; larger glands oblate sjiherical, smaller ones nearly spherical; seg- 
ments 9 to 11, separating ea^iily like tangerine; menihranes thin and tender; axes small 
and compact, about one-half inch in diameter; rag very slight; quality excellent; tex- 
ture very tender and juicy; Havor sprightly subacid, somewhat sweeter than pomelo, 
but with more acid than the tangerine and with a slight l)itter taste derivetl from the 
pomelo; color of pulp, ochraceous-buff to orange buff, differing in this respect from 
both parents; seeds 10 to 15, medium in size; aroma slight, giving suggestion of 
both parents; in general appearance very attractive, resembling small pomelo, but of 
rather darker orange color; tree evergreen, tender, vigorous, and productive, having 
general character of ordinary tangerine; leaves unifoliolate, with comparatively 
narrow petioles like tangerine. 

USES OF THE TANC.ELO. 

The Nocatee tangelo, which has l)een previous]}' described, is not 
familiar to the writers, and they are unable to pronounce on its value. 
The Sampson tangelo, however, is ver}' likely to become an important 
commercial fruit. Those who have tasted it pronounce its flavor 
excellent. Its ver}' attractive appearance and color of flesh, together 
with the ease with which it can be peeled and the seg-ments separated, 
favor its growth in popularity. The bitter taste which is so pro- 
nounced in the pomelo is in the Sampson tangelo reduced to a sug- 
gestion which only adds to its sprightliness. Altogether it is a sprightly 
acid, highly flavored fruit, being not so acid as the pomelo and not so 
sweet as the tangerine, and it is believed that many people will prefer 
it to either of these fruits. It is a vigorous grower and probably produc- 
tive. It is of course no hardier than either parent and can be grown 
onl}' in the orange belts of Florida and California. It is believed that 
the Sampson tangelo will become a popular breakfast fruit, to be used 
by peeling and separating the segments, as in the case of the tangerine, 
and eaten by dipping the segments in sugar. The popularit}' of the 
pomelo, or grape fruit, is due largely to its use as a breakfast appe- 
tizer, and it is recognized as especially beneficial for invalids. It is 
also thought that the bitter element, probably due to some alkaloid, 
furnishes a slight healthful stimulation. The pomelo, however, is too 
bitter and acid to suit the taste of many. The Sampson tangelo, 
being somewhat sweeter and lacking much of the bitter taste, would 
seem to furnish a happy medium between the tangerine and pomelo, 
which would recommend it to man}- who tind the pomelo too harsh. 
In some ways the flavor of the tangelo resembles the most improved 
bitter-sweet orange, ])ut is certainly superior to it. Altogether, it is 
believed that the fruit will occupy a place not now filled ))y any other 
citrus fruit and that it will become valuable for commercial cultivation. 
Its superior quality and the ''kid-glove" character of the rind mark 
it as a distinct and most valuable creatiou. 



238 yearbook of the department of agriculture. 

New Tangerine Oranges. 
[plates xx, xxi, and xxii.] 

One of the primary objects in the citrus breeding experiments was 
to produce hybrids l^etween the common sweet orange and tangerine 
in order to secure a new fruit having the size, quality, and flavor of 
the ordinaiT orange combined with the loose, easily removable rind of 
the tangerine. A few of these hj'brids have now fruited, and two of 
them, crosses of the Dancey tangerine with pollen of the Parson Brown 
orange, have produced fruits which are of considerable value. Both 
of these seedlings were grown from one fruit which was the result of 
a cross made in the grove of Mr. W. K. Trimble, of Braidentown, Fla. 
While the fruits were supposed to be hybrids, the}' nevertheless 
resemble the tangerine orange in all important characters, difi'ering 
from the Dancey tangerine, which was used as the mother parent, 
mainly in being larger and considerably earlier in time of maturity and 
in being of rather better quality. 

THE WE8HART TANGERINE. 

Name. — One of these new tangerines, the Weshart (Pis. XX and 
XXI), is. named in honor of Mr. W. S. Hart, of Hawks Park, Fla., in 
recognition of his valuable assistance in these experiments. Both of the 
new tangerine oranges were grown and fruited under his supervision. 

Description op fruit and tree. — Fruit compressed-spherical, slightly protruded at 
stem end and somewhat depressed at the apex, having the same general form as the tan- 
gerine. Size from 2^ to 3/'j inches in diameter, averaging about 3 inches. Height from 
2\ to 21 inches. Color deep orange red, like tangerine. Surface smooth, glossy, and 
very attractive, much smoother than the Trimble tangerine, to be described later. 
Rind loose, as in other varieties of this group; thin, from /o to J inch thick. Oil 
glands medium size, surface of rind slightly sunken over the largest. Segments 
mainly 10, easily separable. Membranes tender. Axis hollow, from | to 1 inch in 
diameter, star-shaped. Rag tender and in moderate quantity. Quality and texture 
excellent. Flavor sweet, subacid, very juicy. Bouquet characteristic and very 
pleasant. Color of pulp buff orange; cells small like ordinary tangerine. Seeds few, 
from 9 to 15. Tree vigorous and prolific. Foliage branching, and shape of tree like 
the tangerine. Season A'ery early for tangerine. 

The AVeshart tangerine is a delicious fruit of exceptionalh^ line 
appearance and flavor. Its large size, superior quality, and earliness 
indicate that it will prove of great value for general cultivation in 
orange regions. In general it is smoother in surface and rather smaller 
than the Trimble tangerine, but is apparently superior in flavor. 

THE TRIMBLE TANGERINE. 

Name.— The Trimble tangerine (PI. XXII) is named after Mr. W. K. 
Trimble, of Braidentown, Fla., in whose grove the original hybrid was 
produced. The resulting seedling was grown and tested in the grove 
of Mr. W. S. Hart, of Hawks Park, Fla., as was also the Weshart 
tangerine. 



Yearbook U. S. Ospt. of Agriculture. 1904. 



■k^fe 







n9a 



aAti-'f^Lcyx^ 



MOeN A CO . BALTIWORt 



Weshart Tangerine. Natural size. 



Yearbook U. S. Dept. of Agriculture, 1904. 



Plate XXI. 



O 



o 







Yearbook U. S. Dept. of Agriculture, 1904. 



PLATE XXII. 




w 




3>y?a 



ada^fn.O-'H^ 



MOLh A CO . BALTIMORC 



Trimble Tangerine. Natural size. 



NEW CITRUS CREATIONS. 2'6\) 

Pes(RIPTiox ok frcit Axn tkee.— Fruit ronipresyed-yiiheriral, of pame shape as 
the Wei?hart tangerine, and with t^Hghtly protruded stem end and depression at 
apex. Size large, from 3 to 3| inches in diameter and from 2 to 2f inches in height. 
Heavy, averaging ahout 5.6 ounces. Color deep orange red, like Dancey tangerine, or 
slightly darker. Surface somewhat rough and bumpy, in larger specimens similar 
to King orange; frequently with slight grooves running from base to apex. Oil glands 
small, with the surfaceof the rind slightly sunken over the larger ones. Rind loose, 
thin, 5^*2 to J inch in thickness. Segments 9 to 11. ^rend)ranes thin and tender. Axis 
I inch in diameter and hollow. Kag comparatively little for fruit of this class. Flesh 
deep orange yellow and very attractive, tender, and juicy. Pulp cells medium size. 
Flavor sprightly acid and excellent, with pronounced bouquet. Seeds few, averaging 
about 10. Tree vigorous and prolific. Foliage branching, and shape of tree like 
Dancey tangerine. Season of maturity very early for tangerine. 

The Trimble tangerine is a fine large tangerine, the rough, bumpy 
appearance serving to distinguish it from other tangerines, and at the 
same time not detracting from its appearance. In general the fruits 
are somewhat larger than those of the Weshart tangerine, but are 
slightly inferior to them in flavor. 

GENERAL QUALITIES OF NEW TANGERINES. 

The Weshart and Trimble tangerines, it will be seen from the above 
descriptions, differ from other varieties of tangerines primarily in 
being larger and earlier and more highl}' flavored. Fruits of these 
two varieties have been received in some quantity for the past two 
seasons, and have been compared with those of the Dance}' tanger- 
ine, grown In' Mr. W. 8. Hart in the same grove, and with the best 
tangerines that could be procured on the market. In every case 
the}' have been superior in color, size, and flavor. In Mr. Hart's 
grove the\' have uniforml}^ colored up and ripened about two weeks 
earlier than the Dancey tangerine, and it would thus seem that they 
ma}' be highly reconunended for general culture. They have not been 
tested in any other parts of Florida nor in California, and it can not 
be definitely stated what they will do under difl'erent conditions. The 
Dancey tangerine, however, is generally cultivated, and it is believed 
that the new fruits will prove superior to this variety in almost every 
respect. While these two tangerines developed from a fruit of Dancey 
tangerine crossed with pollen of Par.son Brown, they show no clear 
indication of intermediate characters (PI. XXI). They are in every 
respect, .so far as can be judged, true tangerines. The Parson Brown 
orange, which was used as the male parent, is a typical orange and one 
of the earliest varieties cultivated. The new fruits are larger than tho.se 
of the tangerine, and it may be that the large size, and their earliness, 
are qualities derived from the Parson Brown. If it were not for the 
possibility of their lijiving developed from adventive embryos, this 
would be the normal conclusion. It is, however, impossible to deter- 
mine this matter from the characters exhibited by the trees up to the 



240 YEARBOOK OF THE DEPARTMENT 

present time. As the trees mature othei ® ^^^ 

visible which may throw some light upou tuis point. I'racticall}" 
speaking, however, it does not matter whether the new fruits have 
any orange blood in them, so long as they possess valuable qualities. 
The Weshart and Trimble, it should be remembered, are tangerine 
varieties, and, like the ordinar}' tangerine or common orange, can be 
cultivated only in Florida and California, where citrus fruits are 
ordinarily grown. They are unhesitatingly recommended for further 
testing and cultivation in these sections. 



SB 369 
.W35 
Copy 1 




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